Despite leading the US into war and presiding over one of the greatest financial disasters in history, the worst moment of George W Bush's presidency was, he said this week, when Kanye West called him a racist. "It was a disgusting moment, pure and simple," Bush said. "I didn't appreciate it then [and] I don't appreciate it now."

In 2005 West appeared before millions on a live telethon for Hurricane Katrina relief. As Mike Myers stood dumbfounded beside him, the rapper extemporised on race, money and aid efforts, finishing with the now notorious accusation: "George Bush doesn't care about black people." West's outburst helped spur a national debate about the White House's response to Hurricane Katrina.

Five years later, Bush hasn't forgotten. "I can barely write [West's] words without feeling disgust," the former president explains in a forthcoming book. "I faced a lot of criticism as president. I didn't like hearing people claim that I lied about Iraq's weapons of mass destruction or cut taxes to benefit the rich. But the suggestion that I was racist because of the response to Katrina represented an all-time low."

"I still feel that way," Bush told NBC's Matt Lauer. "I felt [that way] when I heard [those words], felt them when I wrote them, and I felt them when I'm listening to them." Bush also recalled telling his wife it was "the worst moment" of his presidency. "It's one thing to say, 'I don't appreciate the way he's handled his business,'" he said. "It's another thing to say, 'This man's a racist'. I resent it, it's not true."

"I wonder if some people are going to read that, now that you've written it, and they might give you some heat for that," Lauer suggested. "The reason is this ..."

"Don't care," Bush said, interrupting.

"Well, here's the reason," Lauer continued. "You're not saying that the worst moment in your presidency was watching the misery in Louisiana. You're saying it was when someone insulted you because of that."

"No, and I also make it clear that the misery in Louisiana affected me deeply as well," Bush said. "There's a lot of tough moments in the book."

While this incident may have bruised Bush's ego, the affair hasn't touched West as deeply. This week the rapper said his gaffe at the MTV Video Music awards in 2009 was "bigger ... than the Bush moment". "There's just so few black men [who] make it that far," he told hip-hop DJ Funkmaster Flex. "That's a responsibility, that's why so many fans of mine were upset because they're like: 'Man, you've got a powerful situation ... You can't be so reckless with your opinion. We can agree with you but you've got to play it in another type of way, because you can't throw away the opportunity.'" Apparently dissing Taylor Swift is more outrageous than taking shots at a sitting president.